HQ Player

[audiofool]

On 11/29/2016 at 3:56 PM, Miska said:

 

That's the way I prefer it too. I don't want to add second layer of acoustics on top of what is already existing in the recording. Some dry studio productions remain to sound dry, but things made in real acoustics sound good.

Wow, I can't believe the improvement, headphones are now usable for me.  Now the problem is which HTRF files to use.  Miska, how did you create your own HTRF files?  Did you use Matlab?  Any quick suggestions to point me in the right direction to create my own filters.

[audiofool]

On 11/29/2016 at 6:30 PM, Miska said:

 

Shouldn't make much difference for 48k, but for hires sources you can enable HF expansion from the Convolution dialog. This will extend the frequency response of the filter flat to the higher Nyquist frequency. Not sure how good it is with crossfeed filters though...

I'm confused, I am using the pipeline setup for htrf ir wav files as suggested previously.  Does the convolution setup HF expansion affect the pipeline setup? 

I have been trying files from the Listen HRTF database with headphones.  I find the tonal balance shifts and the sound isn't as clean.  Probably a question for Miska, but anyone have a workflow for creating ir files, maybe with octave?  I understand that Genelec is coming out with Aural ID - probably expensive for professionals, to create the necessary files.  One place I read suggested that there are only 7 or 8 major ear shapes and with ear to  ear distance measurements it should be possible to create mathematically the impulse file.

[audiofool]

4 hours ago, Miska said:

 

What do you mean by fabric cover? The one with Sennheiser logo on the inside? It is definitely supposed to be as it is and is part of the acoustic design as well as dust protection to avoid contaminating the driver with dust or anything else. But it is taken into account on the design and is part of the measurements...

 

At the moment I'm using Schiit Jotunheim (set to low gain mode) to drive the headphones (inputs are ADI-2 Pro through balanced and Holo Spring 1 through unbalanced). And trying to decide if I should go for Benchmark HPA-4 for it or not...

 

In addition trying to decide about closed design between Sennheiser and AKG as secondary headphone. Now my favorite closed design is Shure SRH1540 that has extremely good price-performance ratio.

 

What about the  Sony MDR 7520? Some of the pro guys like them.  The Benchmark is using the THX AAA technology.  Is this a module?  Is this  like Quad's feed forward technology?

I posted above about creating IR wav files for headphone use, how are you creating your IR files Miska?  Thanks.

[audiofool]

15 hours ago, Miska said:

 

I don't remember the technical details of it, but I remember that it performs extremely well.

 

 

It depends on the purpose, there are many possible ways to do it. In most cases, same software tools used for loudspeaker systems work with headphones too.

 

I'm looking for open source tools like Octave, etc on linux.  I am not doing eq but wanting to create HRTF files, any hints on where to start? 

Also what are your thought on the wavpack format for dsf, any plans to support it?  I know disk space is cheap but the checksum and replaygain features could have some value?

[audiofool]

8 hours ago, Miska said:

 

Octave for example works fine, or DRC-FIR which uses Octave. REW is not open source, but works on Linux too.

 

 

Maybe at some point. However, replay gain is not supported by HQPlayer. And I don't generally like it because it is one form of dynamic range compression.

 

Thanks, I will check them out - I haven't been able to find any tutorials on creating the crossfeed type filters but I will keep looking. 

My idea for replaygain would be to use the tag value  as a reference to preset the volume per song or album not to modify the original file in any way.  Not sure I understand how it is dynamic range compression?

 

[audiofool]

@Miska, more headphone stuff sounds good!  One of my biggest issues is clipped and or brickwalled albums.  If it's something I really like I tend to mess with Audacity clip-fix or one of the other tools like stereotools, etc.   Do you just live with it or do you have a better solution?  How about something like Audacity clip-fix in hqplayer embedded? 

[audiofool]

Attached is an original sine wav hard limited, then hqpplayer pro upsampled with sinc-m and finally clip-fix with audacity.  Clip-fix  is creating data that was not in the original.   Not a purist approach but sometimes the lesser evil.

[audiofool]

57 minutes ago, Miska said:

 

But that data is is not clipped since it is below +-1.0...

 

Correct, it is not clipped in this case but the same results if it was at 0db.  I was trying to show a sine wav that was run through a limiter similar to what is done to some recordings.

[audiofool]

HQPlayer does help with a lot of the clipped material but I do find major improvements with extremely brickwalled material using clip-fix in some cases. It's not the best name since you can adjust the level where it attempts to reconstruct the waveform so it's not just for clipped material.  It also tends to increase the dynamic range a little since it is creating, in some case, new large peaks.  Thanks again.

 

[audiofool]

Has anyone tried the TI isolator ISOUSB211DPEVM  - needs a case but looks easy enough and much cheaper than Intona?

@Miska - do you find the Intona directly connected to your server equal to NAA in sound quality and measurements?

 

 

 

[audiofool]

20 hours ago, Miska said:

 

It is impossible to give a straightforward answer to this, as it depends a lot on the specific NAA hardware and overall system.

 

In case of my livingroom setup, I have two Intona isolators connected to the livingroom server, which are then connected to two DACs. For one of the DACs, the server is running HQPlayer embedded to output DSD256. And for the other DAC the server is operating as a NAA to output DSD512. For both of these cases there's a measurable benefit in doing so.

 

I guess my question really is how perfect are the isolators, for example, if you use something like an rpi4 or a very good server with gigabyte premium usb ports once they go through say the 7055-C can you tell the difference between the rpi and the server?

[audiofool]

1 hour ago, Miska said:

 

It depends... It is pretty hard to give a simple blanket answer to this kind of thing.

 

Sounds like there is still some interaction between the source and the isolator and/or the isolator and some dacs.   I was hoping that the isolator would eliminate all issues with the source.  I understand that the Innota has considerably sophisticated software to work as well as it does.  I may try the TI isolator since it seems they developed a chip for the specific purpose.  I personally find that usb cables, source usb port choice and even alsa buffer settings make a difference.

[audiofool]

A Dither Question:

Would there be any advantage or disadvantage to re-dither 44/16 cd source before processing with hqplayer to sdm output?

My thinking is similar to using apodizing filters to fix issues, maybe adding dither is good in some cases? 

 

 

[audiofool]

17 minutes ago, Miska said:

 

Bad idea... In particular with 16-bit sources.

 

 

It is also applicable to SDM, but in a different way. HQPlayer modulators are dithered, which also means that if you run same source data through the processing multiple times, you will never get same output bitstream twice.

 

I was thinking specifically for 16-bit sources.  In the case where a cd master is truncated to 16 bits instead of dithered - I guess once the damage is done...

[audiofool]

17 minutes ago, bogi said:

 

The same for HS02. It filters+isolates either computer power or external power.

 

User manual states it is able to provide 800mA output current. That's 100 mA less than max. power USB3.0 port can supply. Maybe 100mA is then HS02 power consumption. But that's only my construction.

 

HS02 is USB2.0 compliant when its input port is in data mode (selected by mechanical switch). Computer supplied current through USB 2.0 port is max. 500 mA.

 

 

I had emailed Topping a couple months ago about the power capabilities of the HS02 for use with a usb powered Topping DX1.  The DX1 doesn't draw much power so they said it would work, but still recommended external power supply for the HS02.

 

RME tested the HS02 and said it uses a Mornsun DC/DC converter with about 1nF of coupling compared to the Intona at 10  pf coupling.

I'm not sure if the Mornsun converter is bypassed with an external supply.

 

RME also tested the Hifime USB Isolator V2 2023 - provides 500ma with 71pf coupling.  Not sure I like the unshielded plastic case though.